CN1201483C - Parallel high voltage metal-oxide semiconductor field effect transistor high power steady-state amplifier - Google Patents

Abstract

The present invention relates to a high-power drain grounded common source RF amplifier using a high voltage MOSFET. An RF signal at an input terminal, which is provided relative to the ground, is fed between a grid electrode and a source electrode by a secondary electrode of an isolating transformer and is output from the source electrode relative to a drain electrode grounded. A pair of kilowatt power transistors or a pair of KPTs are used for a-13.56MHZ3KW power amplifier and a topo structure of an RF input driving device for the isolation of a first MOSFET tube core, and the pair of KPTs comprise a plurality of MOSFET tube cores; a drain electrode area of each tube core, which is formed in the most part of the low surface of each tube core, directly, electrically and thermally contacts a conductive copper flange; a source electrode area and a grid electrode area are formed on the tube cores far away from the flat and low surface. One or more chips KPTs can be designed into a stable 2.5KW, 5KW, 10KWRF plasma generator which forms 13.56MHZ. A low-pass/high-pass filter structure is used at an output terminal of the plasma generator for reducing harmonic distortion and harmonic terminal losses.

Description

The parallel high voltage metal-oxide semiconductor field effect transistor high power steady-state amplifier

The present invention relates to such as handling the high power RF amplifier that use the application scenario at semiconductor plasma.The present invention be more particularly directed to a kind of high power amplifier that uses the big tube core multikilowatt of high pressure power transistor.The present invention also can be applicable to other radio frequency applications such as radio communication and induction heating.

In a typical RF plasma generator device, high-power radiofrequency source produces a prefabricated frequency, promptly, the rf wave of 13.56MHZ, and send a plasma case to along a power conduit.This radio-frequency power is provided with a fixing known impedance (that is, 50 ohm) usually.One radio-frequency (RF) driving signal is produced and is fed to a power amplifier, and this power amplifier provides rf wave with a desirable power level (that is, 1.25kw, 2.5kw, 5kw, 10kw etc.).According to this application, this ripple can be such as 2.0MHZ, 4.0MHZ, and the other frequency of 27.12MHZ or 40.68MHZ is provided.

It (is V that traditional plasma RF power amplifier uses operating voltage _CEOr V _DS) the bipolar or RFMOSFET transistor of RF between 40 and 50 volts.Puncture voltage (the V that these semiconductor device have _CEOOr V _DSS) between 100 and 150 volts.The bipolar transistor that is used for these RF amplifiers is commercially available for example Motorola MRF 448, CSF Thomson TH430, and GHZ Technologys200, or philipsBLW96, its typical price is about each 50 dollars.2.5kw amplifier uses 8 of collaborative work in parallel to recommend rightly usually, transistor is used for each one (16 transistor altogether) mutually of recommending right positive and anti-phase part.RF generator bipolar based on low pressure RF or mosfet transistor can realize being used for the good stability and the performance of plasma.The typical amplifier that is operated in about 45 volts this structure is quite insensitive to the special system of being set up, thereby makes it need not provide effective equipment interface to make the user convenient, for example can ignite and keeps plasma for a desirable application.

What recently, pay close attention in RF amplification design person is the research that is substituted the transistorized use of high-voltage MOSFET by low pressure RF bipolarity or RF mosfet transistor.For example, in the U.S. Patent No. 5726603 of granted patent on the 10th March in 1998, this is had disclosure.The initial high voltage MOSFET that plans to be used in the Switching Power Supply has high leakage-source breakdown shock V _DSS, low knot-shell thermal resistance R _OJCWith low drain electrode-source on-state resistance R _DS-ONThese transistors that are made of sizable tube core (that is 100000 square mils) can have a high gain band width product F _TThese big tube cores are designed to have the source electrode of a minimum and the big single chip transistor of gate trace, and are designed to have a plurality of junior units of a large amount of emitters (source electrode) and base stage (grid) line unlike low pressure RF bipolarity and MOSFET tube core.The big die design of high pressure makes the high-voltage MOSFET transistor adapt to production in enormous quantities preferably, and this just switching mode market (switch-modemarket) needed.Its result is for the 1KV puncture voltage (V of standard TO-247 encapsulation _DSS) device, realized that lower packaged transistor cost typically is about 17 dollars or lower.Can realize being about 15 to 16 decibels power gain under 160 volts of DC working conditions during 350 watts of power output at the 13.56MHZ place based on the amplifier of these devices.Employed circuit topography structure is depended in the gain that enters the practical stability of various VSWR loads, and can be 12 to 13 decibels of scopes according to this device producer.Because very little utilized footprint in their current arrangements that needs making space constitute, so the low-cost and very undersized plasma generator of current requirements of semiconductor plasma treatment facility industry.High-voltage MOSFET with circuit topography structure, the surface-mounted technology of use and improved cooling means of innovation is considered to for satisfying the possibility solution that this requirement provides.

Any RF power amplifier need keep or surpass the functional reliability of current device, promptly is based upon the functional reliability of the low pressure RF bipolar transistor on the Amplifier Design basis.Except the use of the high-voltage switch gear mosfet transistor in switching mode circuit topography structure, main possibility comprises the use of the high-voltage switch gear mosfet transistor with RF circuit topography structure.

In the past few years, developed the improvement high-voltage MOSFET transistor that is used for Switching Power Supply.With regard to leakage-source puncture voltage V _DSS, drain to source electrode on-state resistance R _DS-ON, knot-shell thermal resistance R _OJC, total gate charge Qq and draining to the aspects such as voltage change ratio dv/dt of source electrode, the performance of these devices has obtained stable improvement.In U.S. Patent No. 5726603 by background technology and disclosed content description the situation of this technology.

An object of the present invention is to provide a kind of high power RF amplifier of having avoided the defective of prior art and RF power being provided from a compactness and efficient encapsulation.

A more specific purpose provides a kind of RF power generator with good heat radiation and energy supply characteristics, thereby amplifier unit can be stood the thermal shock of responding to from intrinsic power cycle in plasma application.

A specific purpose of the present invention is to be implemented in the improved junction temperature relevant with each tube core on the given multitube core transistor device.

Another object of the present invention provides a kind of high-capacity transistor amplifier, and this amplifier is realized balanced recommending operation and bear good heat balance between the employed a plurality of transistor dies of this amplifier.

A more specific purpose of the present invention is to realize between the tube core in a given multitube core transistor device that improved junction temperature follows the tracks of.

Another purpose of the present invention is to improve power equalization and thermal balance and enter wide load voltage standing-wave ratio (VSWR) scope in a wide power output dynamic range.

According to an aspect of the present invention, provide a kind of high power that is used for amplifying the RF power of an allocated frequency band to recommend the RF amplifier.One drive signal is provided for the RF input, and provides the RF that is exaggerated power waves at the RF output.The DC source voltage that one power supply is provided for multitube core power transistor (i.e. the first and second gigabit power transistor devices, or KPT) (Vs).It for example is the heat of fin and copper earth plate and the conduction flange of electricity that each such KPT device has, and has the multiple chips array that for example is made of four semiconductor elements.It is one smooth than low degree that each semiconductor element has, and constitutes a drain region on than the major part of low degree and leaving describedly smooth to constitute source electrode and gate regions respectively on than the part of low degree.The drain electrode of tube core is placed in and makes they and this flange direct heat and electrically contact on this flange.Therefore, this flange is as drain electrode end and the heat radiation that is used for relevant tube core.

First division device (balanced-unbalanced transformer) device that is connected to the RF input splits into positive part that is fed to a KPT and the anti-phase part that is fed to the 2nd KPT with a RF input drive signal.The second splitter device partly is divided into four isolated signals with the positive of this drive signal and offers the grid of the described first kw of power transistor device.The tripartition apparatus is divided into each grid that four isolated signals offer the 2nd KPT with this anti-phase part.Each of four semiconductor elements of a described KPT is that the grid separately-source electrode input circuit by the corresponding output end that is coupled to the described second splitter device by RF is constituted.These grid-source electrode input circuit insulate with the splitter device with ground DC, thereby it is floated with respect to a KPT flange (and drain electrode).Each semiconductor element of the 2nd KPT has grid-source electrode input circuit separately equally, these grid-source electrode input circuit by DC-isolation ground RF be coupled to the tripartition device it corresponding output end but float with respect to the flange of the 2nd KPT.Combiner apparatus has the source electrode that is coupled to described first and second KPT and is used for the RF that is exaggerated from them is exported the input that makes up.This combiner apparatus provides an output that is combined to the RF output subsequently.This RF amplifier also comprises the filter apparatus that the source electrode of kw of power transistor device is connected to the DC power supply.This filter apparatus includes and is used for blocking from the choke that is exaggerated signal of DC power supply and is used in the bypass band and the RF shunting device of the outer RF energy of band.

According to a further aspect in the invention, a high power grounded drain common source RF amplifier circuit can include an input; One DC power supply; One output circuit; With a high power, high voltage chip transistor, i.e. the transistor core element of a KPT.Include one at this transistor device of this situation or KPT and have the heat of a upper surface and the semiconductor transistor tube core that conductivity flange and has a lower surface, this drain electrode and the direct electricity of this flange and thermo-contact.On away from the tube core of this flat bottom surface, constitute an one source pole and a grid.This amplifier output circuit is connected to this source electrode.One input stage of isolating DC is coupling between input and the grid by RF, promptly between grid and the source electrode, and floats with respect to this flange and drain electrode.This input stage comprises that one has primary coil that is connected to input and the isolating transformer with segregate secondary coil of first and second ends that are connected respectively to grid and source electrode.Preferably, this output circuit comprises that one is used for transmitting and is arranged in the DC that gives the RF signal of putting the RF frequency band and blocks output stage.Preferably RF obstruction DC presents level transistor source is connected to the DC source (VS) in addition.This is presented level and can comprise and be used for the shunting device of bypass RF signal in the band that described source electrode place occurs and outside the band.In addition, this input stage preferably includes at first end of secondary coil and the low resistance between the grid (1-2 ohm) with this transistorized gain of restriction.Be parallel with an optional shunt capacitance to adjust gain in this band with this resistance.This semiconductor element has an input impedance between source electrode and grid, and promptly 5.56 ohm, and this series resistance has a very little resistance value, for example is 10 to 20% of this input impedance.Leakage-grid feedback circuit is connected to first end and this grounded drain of transformer secondary output coil.This leakage-grid feedback circuit preferably includes the resistance and the electric capacity of serial connection.The grid source is returned resistance and is placed between source electrode and the grid, and has one and compare with this input resistance and to want big many ohmic values (35-40K Ω).This input stage can comprise that also one is in series by electric capacity and resistance and grid-source terminal circuit of constituting between grid and source electrode.

This transistor device, that is, kw of power transistor or KPT are high-voltage MOSFET hybrid circuit devices.Best this device that uses is existing in the application of the pending trial Application No. No.08/957100 of application on October 24th, 1997 in RF amplifier of the present invention discloses in detail, and has a common licensee.In the content disclosed in this patent application here as a reference.

10kw RF power generator can use recommending constituting of four such KPT, just always has 8 KPT in this power-amplifier stage.Each KPT has four high voltage MOSFET tube cores, and their drain electrode is directly connected on the actual in its lower section copper coin as a radiator.Be a molybdenum sheet between each tube core and copper coin,, just enter RF power on-off prevents the difference of the thermal coefficient of expansion between copper and the silicon during cycle influence when this generator during power cycle, to keep this tube core.All 8 KPT are positioned in one and are referred to as usually on the water-cooled copper radiator of coldplate, and when described device works in overdriving during classification " C " in grounded drain/common source structure, each of two KPT is recommended and is about the 3KWRF power output to providing.This structure can be improved thermal design by traditional insulating surface (being generally BeO) of eliminating between drain region and copper supporting bracket.This means directly ground connection of all four drain electrodes (being the drain electrode of each tube core).

Being used for these four source electrodes of recommending right each half (each KPT) directly is connected in parallel.Being used for these four grids of recommending right each half is impedance matching (increases), and by isolating transformer and by parallel connection.This just makes and improved the junction temperature tracking greatly between four tube cores of a given KPT in whole power output dynamic range, and improved the various supported V SWR that can be run in plasma treatment.Suggestion uses the high power series connection resistance of a not bypass or part bypass to be implemented in the unconditional stability in the whole dynamic range to each MOSFET tube core under all supported V SWR conditions.

After this array output, provide a dissipation harmonic termination by a high pass filter in the input of this low pass filter.This has just reduced the voltage difference of gate-to-source, and for each MOSFET tube core with this grid-source voltage remain on given restriction (± 30V) within.

After a in conjunction with the accompanying drawings most preferred embodiment is elaborated subsequently, can be to the present invention above-mentioned and other purpose, characteristic and advantage have more comprehensively and understand.

Fig. 1 shows the single-end circuit of RF power amplifier according to an embodiment of the invention, and this circuit working is in for example C class and have grounded drain/common source structure;

Fig. 2 shows the similar circuit of the source ground/common source structure of comparing with Fig. 1 embodiment;

Fig. 3 shows another embodiment, there is shown the example with floating outstanding DC grid bias that is used for category-A or the work of AB class;

Figure 4 and 5 show employed four-core sheet kw of power transistorized schematic diagram and the plane graph relevant with the present invention;

Fig. 6 comprises Fig. 6 A and Fig. 6 B, is the circuit diagram of the high power RF amplifier of push-pull configuration according to another embodiment of the present invention;

Fig. 7 has been to use the entire circuit figure of the 10KW RF generator system of the principle of the invention;

Fig. 8 is the dissipate circuit diagram of low-pass/high-pass filter of the outer harmonic energy of band of be used for relevant with the present invention.

Referring to accompanying drawing, at first consult Fig. 1, provide a single-ended RF amplifier circuit that works in " C " class as a grounded drain/common source crystal amplifier.This amplifier uses a single-chip or single die MOSFET power transistor Q ₁But, this transistor Q ₁Also can be used as each tube core of multicore sheet KPT, and be used to explain the advantage and the work of interlock circuit.Transistor Q ₁Have a drain electrode port of ground connection and be used for grid G and the separation end of source S by means of contacting with this flange.

Here this amplifier is intended to provide one to give that to put frequency be that 13.56MHZ, power level are that 350 watts and given output impedance are for example 50 ohm RF power.This circuit working is at the 160V dc voltage and have the power gain of about 13dbRF.The load line of drain electrode-source electrode is set to 32 ohm, has the gate-to-source differential impedance that is about 5.56 Ω.13.56MHZ drive signal is added to single-ended input RF _IN, be the input impedance of 22 watts power and 50 Ω here.Input capacitance C1 is used for compensation input induction reactance.Isolating transformer T1 has that an elementary and end that is connected between input and the ground is connected to the grid of transistor Q1 and the other end is received the secondary coil of source S.The turn ratio of this transformer T1 is 3: 1, and the input impedance of 50 Ω and the gate-to-source differential impedance of 5.56 Ω are complementary.Be included in end of transformer secondary output and the series connection resistance between the grid G and be used for improving job stability in the wide region of VSWR.This is a high-power resistor, has to be about 1 to 2 ohm ohmic value.By resistance R ₂And capacitor C ₂Drain electrode-grid the feedback circuit that constitutes is connected in series between the end of secondary coil of drain D (that is ground) and transformer T1.This feedback circuit is preferred for input one output VSWR, and provides steady operation to high VSWR.Capacitor C 2 is as the DC blocking function, and the value of resistance R 2 depends on gate-to-source impedance (, for example being 5.56 Ω) and drain electrode-source impedance (, for example being 32 Ω), power gain, and the stability requirement of various supported V SWR here here.

The tandem compound of resistance R 3 and capacitor C 3 provides one to be used for the gate-to-source RF end of steady operation to high VSWR.If used DC biasing (this will discuss) then capacitor C 3 is used as DC blocks electric capacity in embodiment subsequently.The value of resistance R 3 is preferred for desirable VSWR and RF gain.Under the situation of transless T1, for stablizing of DC, resistance R 4 provides a gate-to-source loop.This resistance can have with respect to this gate-to-source impedance wants big many values (35-40K Ω).

One optional shunt capacitance C4 and resistance R 1 arrangement in parallel.The value of this electric capacity is selected to the desirable frequency of bypass (for example, 13.56MHZ), thereby only makes the outer energy of band be reduced.But for a lot of plasma application, if can obtain enough gains at desired frequency place, then this capacitor C 4 preferably is omitted.

The RF output network has an inductance L 1 and capacitor C 5, and node between the two is connected to source S.This inductance and electric capacity combination L1-C6 constitute a resonator to close the output capacitance of transistor Q1.Capacitor C 5 is delivered to output RF with the 13.56MHZ output wave _OUTOutput transformer T5 be inserted between capacitor C 5 and the output with will drain-source impedance (32 Ω) is complementary with output impedance (50 Ω).Here transformer T5 has 4: 5 the turn ratio.

Fig. 2 shows a kind of circuit that is similar to Fig. 1 except that the non-ground connection drain electrode of using a routine.Represent by identical label with element similar among Fig. 1.Circuit shown in Fig. 2 is the single-end circuit of source ground amplifier of " C " class of a kind of being used for.Source ground MOSFET circuit is circuit typical and that often use in the RF plasma generator.The circuit of this structure can be stable in whole dynamic range to various supported V SWR work.Here, transistor Q1 is a kind of between this tube core and conduction flange, promptly is mounted with the standard low level MOSFET of a BeO insulator between drain electrode and the radiator.But, for the purpose of comparing with this circuit of the present invention, this transistor Q ₁Can consider that one has the high voltage MOSFET of a BeO insulator between drain electrode and radiator.A DC drain voltage (+V who provides is provided sort circuit _D), for example be+160V and 350 watts of RF for example are provided at the 13.56MHZ place output to have the drain efficiency of 15db power gain and about 70%.The input and output impedance of this circuit is changed to 50 ohm.Load line is 32 ohm (drain electrode-source electrodes).Impedance between grid and the source electrode is 5.56 ohm.The embodiment of like Fig. 1 is such, and resistance R 4 provides the gate-to-source loop under the transformer T1 situation lacking, and helps to determine DC stability.Resistance-capacitance combination R3-C3 provides the one grid-source class RF end that is used at high VRWR steady operation.When using the DC biasing, capacitor C 3 is that a DC blocks electric capacity.In order to gain at high VSWR steady operation and desirable RF, the value of R3 can be by optional.

Resistance-capacitance combination R1-C4 provides a series connection to gain input impedance to adjust gain and the outer low-frequency gain of reduction band in the band, so that realize various unequally loaded steady operations in the different capacity level range.For required RF gain, the desirable frequency of the common selected bypass of the value of capacitor C4, for example 13.56MHZ.

Resistance-capacitance combination R2-C2 provides drain electrode-grid feedback, and capacitor C 2 is blocked electric capacity as DC.The value of feedback resistance R2 depends on gate-to-source impedance (that is 5.56 Ω), drain electrode-source impedance (that is load line=32 Ω) and power gain.In addition, the value of resistance R 2 is best for input-output VSWR and steady operation to high VSWR.

DC presents net and is connected between DC power supply and the drain electrode end D.Present in the net at this DC, inductor-capacitor combination L1-C6 constitutes a resonator to close the output capacitance of MOSFET Q1.Inductance L 1 can have the inductance value that is about 0.5 μ H.Capacitor C6 can turn back to the RF energy ground and constitute a circulation loop by drain electrode-source electrode output capacitance between 0.1 to 0.47 μ f.In order to be operated in a given drain voltage V _D(for example+160V), be best here, for this inductance L 1 of drain electrode frequency in desired output (350 watts).Present net at this DC, inductance L 2 is RF chokes, and capacitor C7 is that a RF by-pass capacitor (that is 0.22 μ f ceramic condenser) and C8 are low frequency bypass capacitor (that is 22 μ f electrochemical capacitors).Detect resistance R 5 and be used to import the measurement of DC electric current, and have low fixedly ohmic value (that is 0.01 Ω).Resistance R 6 is electric charges that a bleeder resistance gathers on drain electrode end with leakage, thereby protects MOSFET and guarantee personal safety.

Here, the RF output network is connected with the drain electrode end of transistor Q1.In this output network, capacitor C5 is that a DC blocks electric capacity.Transformer T2 is an output RF transformer, and has 1 32 Ω drain electrode-source impedance are matched the turn ratio of 50 Ω output impedance.

Because this transistor drain insulate mutually with radiator and flange, so compare each some reduction of transistorized power with the amplifier of Fig. 1.In addition, owing to there is the BeO insulator, in a plurality of parallel amplifier architectures, the tube core that is used for each amplifier MOSFET will have different heat loads.As previously mentioned, Fig. 2 only provides a kind of comparable source ground circuit, but in practice, does not have the large tracts of land that is used for desirable power output relevant with plasma application and temperature cycles, the high voltage MOSFET that are applicable to sort circuit.

Fig. 3 shows a kind of single-end circuit that is used for grounded drain/common source work.Sort circuit and above-mentioned circuit major part shown in Figure 1 are similar, and components identical is represented with similar label.The formation of sort circuit can be used for " A " class work or is used for the work of " AB " class, and can be used as the AB class that is used for 1.25kw, 2.5kw, 5kw, 10kw RF generator system and recommend driving stage.Here, transistor Q1 is as shown in Figure 1 a high voltage MOSFET, and the electrical characteristics that have are similar in the described electrical characteristics of corresponding mosfet transistor shown in Fig. 1.Appropriate transistor selects to depend on output of RF power and gain requirement.The different add ons that are used to provide a DC bias voltage that have been to use with Fig. 1 embodiment principle.Here, have a very fractional value resistance R F (0.5-1 Ω) who is connected in series mutually with source terminal for DC and RF are stable.This output is to obtain after source resistance R7.The biasing of this mosfet transistor Q1 can realize in several ways, demonstrated wherein a kind of here.18 volts of DC power supplys (not shown) that float have been to use in the approximate diagram in this embodiment here.This power supply is connected between gate input and the source electrode return terminal road and has and is used for the required circuit element of this application.Here the required circuit of a grounded drain RF MOSFET that is used for as can be seen setovering not is inessential or obtains significantly by any way, has provided the more simple bias structure that is used for source ground MOSFET circuit here.As shown, so owing to big this biasing networks of RF voltage fluctuation of appearance on source electrode return terminal and gate input is the expansion of some element.

Here, this amplifier input impedance and output impedance are set to 50 Ω.Source electrode-ground load line is set to 50 Ω.Differential impedance between grid and the source electrode is 12.5 Ω.It should be noted that secondary coil by transformer T1 and resistance R 4 source path and gate terminal are added with-160V DC current potential.The complexity of this biasing circuit results from the impedance that need be used to regulate different voltages between source electrode and the grid, has the source voltage level of continuous fluctuating there.

Like previous embodiment is such, resistance R 4 for DC stable and protection as gate-to-source DC loop or on draw and provide.If be interrupted by the DC path at the secondary coil of this transformer T1, then resistance R 4 avoids MOSFET Q1 to be damaged by too high gate-to-source difference dc voltage.

Resistance-capacitance combination R3-C3 provides a gate-to-source end that is used for steady operation under high VSWR state in whole dynamic duty scope.Capacitor C3 is that a DC blocks electric capacity, and resistance R 3 is best for stable and RF gain.Resistance R 1 is a serial connection grid input resistance, and the resistance that has is about 2 Ω, and for required to high VSWR at whole dynamic range steady operation.Resistance R 1 is by capacitor C 4 bypasses in this embodiment, and the value of this capacitor C4 is best for the RF gain with for the stability of the set-point (its value can be about 0.5-1 Ω) of source resistance.

Resistance-capacitance combination R2-C2 provides drain electrode-grid feedback, and capacitor C 2 is used for DC and blocks.The ohmic value of resistance R 2 is selected for general input and output impedance and RF power gain at first.Resistance R 2 also is best for be stabilized to high VSWR in whole dynamic range.In this source electrode electric power network, L1-C6 is in fact as the source electrode-drain electrode output capacitance of a resonator to close MOSFET Q1 in the inductor-capacitor combination.Capacitor C6 block as DC and provide a RF over the ground path with bypass RF signal.

Here also show a DC block-condenser C9, this capacitor for example is about 1 μ f200V.Between the second secondary end of source S and transformer T1, be serially connected with a steady resistance R7.This resistance is 25 watts of resistance of 0.5 to 1 Ω preferably, are placed on the flange.

Output signal, is blocked capacitor C 5 by DC and is obtained after serial connection source resistance R7 from source S.Embodiment is such as described above, has the load line of 50 Ω.At this input, transformer T1 combines with building-out capacitor C1 grid level-extreme difference branch is impedance-matched to 50 Ω.This transformer T1 has 1: 2 the turn ratio so that 12.5 Ω gate-to-source differential impedances are matched at input RF _IN50 Ω.

In this embodiment, need there be the RF filter network, promptly on a branch road, be connected to coil L3, resistance R 8 and the capacitor C 10 of grid level G, with the coil L4 that is connected to source S, resistance R 9 and capacitor C 11, avoiding drain electrode-grid feedback by the gate bias network, it is actually with desirable R2-C2 gate-to-drain feedback network and is in parallel.Variable resistor R10 and grid input row are in series and are used for bias adjustment, are provided with complementary resistance R11 symmetrically in the source path row.Capacitor C12 and C13 are that the RF shunt capacitance is to guarantee not having picture to turn back to this floating power supply or enter this gate-to-source end from the RF signal of the spurious signal of certain external source.Resistance R 12 and R13 are selected for required gate-to-source threshold window, and it can change between 2 to 4V for most of high-voltage MOSFETs.

The effect of inductance L 2, capacitor C 7, C8 and resistance R 5, R6 is as the foregoing description.

Referring to Figure 4 and 5, kw of power transistor 10 has a metal rim 12 or a basal plane, and it is positioned in one and can constitutes on the suitable radiator (not shown) of chassis portion of amplifier.This transistor is a quadrangle or the design of four-core chip arrays, be mounted with four transistor chips or tube core 14a, 14b, 14c and 14d on flange 12, and each drain region D is grounding to flange 12.Each transistor dies have separately grid G 1 to G4 and source S separately 1 to S4.As shown in the figure, these source electrodes also link to each other with source path lead-in wire SR1 to SR4.Each side of this flange provides groove or hole 16, and is connected on the relevant radiator by hole 16.Plastics, pottery or metal can cover this four tube core 14a to 14d, and make two ends of this flange 12 be in exposed state.This flange 12 itself is connected to the ground of external RF circuit as each grounded drain line or electrode of four transistor units by additional rectangular line 28.Rectangular source electrode line 22a to 22d, gate line 24a to 24d and source path line 26a to 26d (these lines are connected to source electrode line separately) connect the RF electrode tip.These lines 22,24,26,28 are curled near the outlet of each side at them of this housing separately line is provided distortion reduce.In the application of the unexamined patent application No.08/957100 that this device and several modification were applied on October 24th, 1997 more detailed explanation is arranged.

Referring now to Fig. 6 (constituting),, it is right that power amplifier 100 has used based on recommending of KPT Q1, the Q2 of C quasi-mode work by Fig. 6 A and the 6B that put together.Upward half (transistor Q1) is shown among Fig. 6 A and is shown among Fig. 6 B with following half (transistor Q2).Here, recommend Q1, Q2 are provided separately each MOSFET tube core and the grid of isolating input is used for improving die temperature and follows the tracks of.Whole recommending provides 3000 watts and 11dbRF power gain when 72% efficient to being designed to.

The Q1 of each KPT, Q2 constitute this and recommend right half and have four high-voltage MOSFET tube core Q1A, Q1B, Q1C, Q1D and Q2A, Q2B, Q2C, Q2D respectively, and their drain electrode is by relevant copper flange 112 direct ground connection.Each is the directly parallel connection of source terminal of the tube core of KPT separately, and promptly being connected in parallel forms one 9 Ω impedance interfaces partly to recommend for each.As for gate terminal, each tube core Q1A to Q2D has an independent source electrode-grid circuit, thereby realizes that independently DC is stable, RF is stable and impedance matching.Grid is subsequently by a pair of splitter/isolating transformer parallel connection.Be similar to according to Fig. 1 described and shown in such each tube core one gate-to-source input circuit is provided.Here, the label that this resistance, electric capacity and inductance element given are common, each numeric suffix corresponding to relevant KPT (Q1 or Q2) or character (A is to H) corresponding to the tube core of being correlated with.

Has separately gate-to-source input circuit 106A to 106H for each of the gate terminal of MOSFET tube core Q1A to Q2D.Each all has and is used for the stable gate-to-source resistance R 5A to R5H of DC.In whole dynamic range the good RF that enters 50 Ω loads stable be drain electrode-grid feedback series resistance-capacitor bank R3A by separately, C3A to R3H, C3H realizes.Entering the RF of high capacity VSWR stable in whole dynamic range is that C4H realizes by gate-to-source series resistance capacitor bank R4A, C4A to R4H.Comprise opening/short-circuit condition and to enter the RF of high capacity VSWR stable on all phase places be to utilize not by the series connection resistance R2A of bypass, R2B ... R2H realizes.

Impedance transformation from the difference to the common mode is by transformer T3A, T3B ... T3H realizes.The secondary conductively-closed of each of these grid transformers to be avoiding any magnetic core heating, this heating can owing to the RF voltage between second level coil and ground different heat flux caused.The turn ratio of these transformers T3A to T3H is 3: 1; And the input impedance that produces 100 Ω at the input of the primary coil of these transformers.Since long grid and source electrode track on relevant printed circuit board (PCB) and with capacitor C 2A, C2B ... C2H is placed in and is used for compensating this induction reactance between the primary coil.

At input RF _INWhen input drive signal was added to balanced-unbalanced transformer transformer T1, this balanced-unbalanced transformer transformer split into forward and reverse phase with drive signal.The coil of transformer T1 is presented to last half (that is KPT Q1) and another coil is presented down half (that is KPT Q2).This input drive signal is provided at the 13.65MHZ place, and power is 175 watts, and input impedance is 50 Ω.These two balanced-unbalanced coils intercouple, and each has the input impedance of one 25 Ω.Half of recommending for each has two splitter/isolating transformers, promptly is used for transformer T2A, the T2B of half and is used for down half transformer T2C, T2D.The input impedance that is used for each splitter/isolating transformer is 50 Ω, and their common connections consequently have 25 Ω interfaces of balanced-unbalanced transformer output, and balanced-unbalanced transformer output is 25 Ω still.Transformer T2A to T2D divides this RF input drive signal to provide 100 Ω impedances output to mate the primary consumer of corresponding transformer T3A to T3H.The sort circuit formation sends to tube core Q1A to Q1D and Q2A to Q2D with the balance drive current, even these tube cores are fully mated.Isolation resistance R1A, R1B, R1C and R1D be connected each splitter/isolating transformer T2A, T2B, T2C, T2D two ends to realize the mating end impedance.

Have the output impedance of 9 Ω at each KPT of the source electrode place of parallel connection, and combine with an output balanced-unbalanced conversion transformer T4, the combination layer impedance is 18 Ω.Output transformer T5 becomes 50 Ω load impedances with 18 Ω impedance matchings.Reason for this reason, the turn ratio of this transformer T5 is 3: 5.RF output capacitance C5A and C5B are selected with by interested frequency, are a frequency band that is about 13.56MHZ in this example.

Each recommend half have a source electrode in parallel with KPT and be connected to source voltage (DC feed network Vs).In each DC feed network, it (that is 13.56MHZ) is maximal efficiency, that the drain electrode of making up by closing-source electrode output capacitance makes resonator inductor L1A, L1B be preferably desired frequency.Capacitor C6A, C6B provide a RF passage channel and an obstruction DC to ground to supply with.RF choke L2A, L2B, capacitor C7A, C7B; Capacitor C8A, C8B; Resistance R 6A, R6B; Carry out the similar functions of like L2, C7, C8, R6 and R7 as shown in Figure 1 with resistance R 7A, R7B.

Illustrated that above this recommends right situation in the steady operation in entering the whole dynamic range of all VSWR.This recommend to structure realized improving efficient and among four tube cores of each KPT fabulous die temperature follow the tracks of, even the MOSFET tube core is mated equably, even with the printed circuit board (PCB) Butut relevant with different die is not accurately identical or symmetrical, because space constraint also this result may occur.Here discuss and show division and isolate gating, it should be noted that the improvement that temperature is followed the tracks of in a direct gating range of structures in parallel of amplifier.Just, when this gating drive signal was isolated by division, the temperature difference Δ T from the tube core to the tube core was improved to Δ T=10 ° from Δ T=80 °.Here provide this conception of species, promptly realized the benefit that the benefit of conventional common combination has brought the output transformer number of components to reduce.In addition, DC and the RF stabilizing circuit permission steady operation in whole dynamic range that is used for each MOSFET arrives various supported V SWR, promptly 1.0: 1.1.5∶1，2∶1，3∶1。In all phase conditions, to open circuit/short circuit.

For power output is increased to 10KW from 3KW, shown in Figure 7 as what be made up of Fig. 7 A and 7B, some KPT are to being placed by push pull mode.Driving amplifier plate 30 have one with RF input RF _INThe attenuator 31 that links to each other, follow by low level driving amplifier 32, " A " class recommend to 33 and " AB " class recommend amplifying stage 34.700 watts of drive signals that produce later are separated into four 175 watts of drive signals in division level 35, per two 175 watts of drive signals are provided for each power amplifier plate 40A and 40B.Each power amplifier plate 40A, 40B have two groups of transistorized 3KW of kw of power and recommend (Q1, Q2 and Q3, Q4), and each has the layer impedance of 18 Ω.Here, the output of two couples of Q1, Q2 and Q, Q4 is combined by 2 road inphase combiner 42A, 42B, exports 6KW respectively in 9 Ω output impedance.Output on each plate is matched 50 Ω by the dual transformer of cascade represented transformer 44A, 44B in 1.1: 1 VSWR.Here, the turn ratio that has of first transformer is that the turn ratio that 2: 3 and second transformer have is 2: 3.These two 50 Ω outputs are combined in 2 road inphase combiners 48 of combiner/low pass filter plate 46.This two road inphase combiner has 1.1: the terminal impedance that is combined 25 Ω among the 1VSWR.Here combiner includes a transformer that this impedance conversion is become 50 Ω with 3: 4 turn ratioes.

For maintenance-55dbc in whole dynamic range or be lower than-and the harmonic wave capacity of 55dbc, the output channel of FL-network 50 and 52 by being combined, this passage comprises the 7th rank 0.01db passband fluctuation Chebyshev (Chebyshev) response bandpass filter 52.It has the interruption frequency of a 16.27MHZ, has the 3db point at the 18.64MHZ place.Second harmonic from this filter suppresses to be generally 42db.Third harmonic suppresses to be generally 65db.But for the RF generator in plasma application, it is not enough suppressing harmonic wave by this low pass filter, and each step must consume this harmonic energy.The consumption of harmonic wave is ended to realize that by high pass filter 50 high pass filter 50 is added in the input of this low pass filter.This low-pass/high-pass has constituted a duplexer.In this structure, be absorbed and can not influence main 13.56MHZ signal significantly at the resistance terminal harmonic wave of this high pass filter.In power amplifier of the present invention, the high pass filter of termination has protected the MOSFET tube core to avoid infringement from excessive grid-source voltage difference.In addition, it is poor that the earth-current relevant with these harmonic waves will be derived excessive Instantaneous Grid-source voltage, thereby damaged this MOSFET.Just, if harmonic wave is dissipated inadequately, then this grid one source pole can surpass ± 30 volts of maximum Δ specification grid-source voltages.

This high pass filter 50 has the 5th rank 0.1db passband fluctuation Chebyshev response in the present invention.The interruption frequency of this high pass filter is 25.67MHZ, has the 3db point at the 21.71MHZ place.

Show high pass filter 50 and low pass filter 52 among Fig. 8 in more detail, low pass filter 52 is by capacitor C21, C22, C23 and C24 and inductance L 11 in Fig. 8, and L12 and L13 constitute, and the RF ripple of the purification that is exaggerated is provided at 13.56MHZ.This high pass filter 50 is made of series capacitance C25, C26 and C27 and shunt inductance L14 and L15.Comprise second, third, harmonic wave such as the 4th, the 5th be sent to 50 Ω resistance for dissipation RL by the bypass higher frequency components.This high pass/low pass filter structure is a duplexer, makes the harmonic distortion minimum and sets up a dissipation harmonic wave end.This dissipation harmonic wave end has protected this high-voltage MOSFET to avoid the infringement of excessive grid-source voltage poor (± 30V is maximum prescribed limit) by this high pass filter.

Directional coupler 54 is designed to handle has 46dB forward direction coupling and greater than the 10KW RF power of 40dB directivity.Coupler 54 has forward direction and reverse hole, and the band pass filter network of dress had ± 10% bandwidth in first had, ± 0.02dB fluctuation and suppress greater than the harmonic wave of 25dB.This directional coupler 54 can be based on and utilize high Q and the designed transformer of moderate mu (40perm) Ferrite Material maybe can be the part transmission line design.

Medium drive level 33 provides 30 watts and has the 17dB power gain when 1dB compresses, it includes the high voltage MOSFET of a pair of symmetrical operation.Each MOSFET is biased in " A " quasi-mode of 0.5 ampere.Biasing is to realize by means of 18 volts of DC power supplys that float as shown in Figure 3.The output driver level includes two high-voltage MOSFETs of a pair of four symmetrical operations.Each MOSFET is biased in " AB " class of 0.25 ampere.This is recommended 700 watts of outputs when 2dB compresses, and has the 13dB power gain.This output is divided into four the tunnel by homophase splitter 35 subsequently.

The output of this low pass filter is fed to RF output RFOUT by a two-way coupler 54 subsequently.

Also have other auxiliary and peripheral cell, for example power supply, control and transducer etc., these elements all are included in this RF generator system, but these elements are the elements outside the scope of the invention.But these add ons are comprised among Fig. 7 for complete purpose.

The high voltage, the high power MOSFET that are used in most preferred embodiment of the present invention can have following characteristic: maximum drain-source breakdown voltage V _OSS=1000 volts; Maximum drain current I continuously _D=11 amperes; Grid-source voltage V _GS=± 30 volts; Threshold voltage of the grid V _G-TH=2 to 4 volts; Forward transconductance G _FS=7 to 11 Siemens (Siemens) maximum drain-source electrode on-state resistance R _DS-ON=1 ohm; The maximum housing thermal resistance R that connects _OJC=4 ℃/watt; Input capacitance C _ISS=2460pf (typical case); Output capacitance C _OSS=360pf (generally); Oppositely transmit capacitor C _RSS=105pb (generally); Total gate charge Q _q=90nc (generally); The gate-to-source charge Q _Gs=10nc (generally); With the gate-to-source charge Q _Gd=50nc (generally).

For tube core to the gate-to-source threshold voltage symmetry of consistency between four tube cores of KPT of tube core should be within about 0.2 volt.Its as a result all four tube cores connect simultaneously.For drain efficiency is followed the tracks of, the balance of the drain electrode between four tube cores of KPT-source electrode connection resistance should be within 8%.The balance of the forward transconductance between four tube cores of KPT should be within 1 Siemens.For the efficient performance on favourable RF power gain, the DC characteristic of four tube cores of each KPT will be by coupling on this tube core level.This RF performance will be by verification and measurement on this KPT level.RF gain balance between four tube cores of given KPT will be within 0.5db.Drain efficiency balance between four tube cores of given KPT should be within 1%.This gate-to-source threshold value of momentary connection for each MOSFET in given KPT should match within 0.2 volt.Smooth for the load of each MOSFET tube core, gate-to-source is connected resistance should be within 8%.For each tube core on given KPT provides the smooth of electric current, forward transconductance should be within 1 Siemens.The coupling of these three DC parameters preferably utilizes the tube core conversion to realize among this MPT manufacture process.Four tube cores for this KPT will be selected among identical wafer, and select from the adjacent position this wafer.Will be measured for the DC characteristic each tube core on this KPT level such as gate-to-source threshold voltage and the drain electrode-source electrode connection resistance with RF gain and drain efficiency.

Right for recommending of a given as mentioned above generator application, each correspondence of KPT is mated.In other words, four tube cores from a KPT will be from the adjacent chips choice of location,, have so also from the adjacent chips choice of location for the tube core of another KPT with respect to RF gain, efficient, in the optimum performance that temperature is followed the tracks of between KPT of current tracking between the KPT.Δ RF gain between four tube cores of this KPT should be within 0.5dB; Δ RF efficient between four tube cores of this KPT should be within 1%.KPT with higher average gate threshold will be used for the forward wave part, and it is directly coupled to the input balanced-unbalanced transformer, and the KPT that has than the harmonic(-)mean gate threshold will be used for the backward-wave part, and it is to be coupled inductively.Here, the difference between forward wave and the backward-wave KPT should be about 0.1dB to 0.2dB.

This input balanced-unbalanced transformer transmission line design is preferably used the bifilar winding that twines, and has the characteristic impedance of 50 Ω in the FERRITE CORE of a moderate permeability (μ=40) and high Q (low-loss).This input balanced-unbalanced transformer splits into forward and the reverse phase ripple that each is 25 Ω impedances with input signal (50 Ω impedance).This forward phase ripple is split into the signal that four amplitudes and phase place all equate by a part that is directly parallel in the splitter on this input and has interior dress isolation greater than 25dB.Each of these splitters all loads (125 permeabilities, high Q, low-loss) transmission line design according to a ferrite, uses to twine bifilar strand circle and have 100 Ω characteristic impedances.The input impedance of each splitter is 50 Ω, and two inputs are at 100 Ω.Parallel impedance at two forward phase splitters of this input is 25 Ω, and the output impedance of the input balanced-unbalanced transformer of it and forward phase part is complementary.

This reverse phase partly has corresponding characteristic and attribute.

Each of forward phase ripple and reaction position ripple is split into four ripples to drive each MOSFET tube core of KPT separately.The input driving circuit that is used for each tube core is identical, includes following part, promptly input transformer, series connection input resistance (can not by bypass or partly by bypass), DC end or on draw or source electrode-grid RF feedback.Each MOSFET tube core has one and separates input transformer, has the input impedance of 100 Ω.Elementary incoming wave at this transformer is for ground, and is for source electrode (or signal output level) at the secondary output wave of this transformer.Output impedance with respect to this transformer of source electrode is 11 Ω.This transformer is the transformer coupled design of a ferrite load (μ=125, high Q, low-loss), and input is 3: 1 to the turn ratio of output.Each MOSFET tube core has its series connection input resistance, has the value that is installed in from 1 to 2 Ω scope on one 25 watts of flanges.This just provides the stability that enters the gamut of VSWR for fully dynamic output power range, i.e. open circuit-short circuit-all states.Require this resistance not by bypass or partly by bypass according to this RF gain and rf robustness.

Each MOSFET has its input RF end between grid and source electrode.This end is made of series resistance-electric capacity combination, and in fact the electric capacity that is had block as DC.This resistance value is about 50 Ω, is about 4.5 times of 11 Ω layer impedances.This resistance helps in whole dynamic range steady operation to high VSWR.The selection of its value is compromise between RF power gain and RF are stable.Each MOSFET tube core also has its DC end resistance that is positioned between grid and the source electrode.This resistance have 30 and 40K Ω between value, and the DC by the input transformer secondary coil connect provide under the interrupted situation DC stable and on draw.In addition, each MOSFET tube core has its source electrode-drain electrode RF feedback network, and this network can comprise a resistance-capacitance tandem compound, and the electric capacity that has blocks as DC.In this case, this resistor can be that the 150W flange is settled, and the value of this resistance is in the scope of 400 to 560 Ω, and this depends on the requirement of RF power gain and stability.This network provides the RF I/O coupling of various loads and RF output to stablize.The actual value of this resistance is in required RF power gain with to trading off between the RF output stability of all phase conditions, comprises all states of open circuit, short circuit and load.

The output of their four drain electrodes that this KPT had, that is, source electrode directly is connected in parallel by a printed circuit board.These connect symmetry as much as possible.The output of forward phase KPT constitutes a forward phase ripple, and its value is that the output of 9 Ω layer impedances and reverse phase KPT correspondingly constitutes a reverse phase ripple, also is 9 Ω layer impedances.

For each KPT, this array output electric capacity (that is, source electrode-capacitance of drain) is by a resonant circuit dynamic compensation that combines with the electric capacity that blocks as DC, and allows the RF short circuit current to ground.The scope of the value of this inductance is between 0.3-0.5 μ H and be to use high frequency, low consumption, the pulverous core material of low permeability to realize.This inductance value is best and improvement that 5-8% efficient is provided for RF efficient.

Forward and reverse phase ripple are combined by the output balanced-unbalanced transformer transformer with 9 Ω input impedance and 18 Ω output impedance.This output balanced-unbalanced transformer transformer is to use two transmission line type ferrite load devices (μ=40, high Q, low-loss) that twine of 18 Ω characteristic impedances.By around this transformer, using high voltage, high electric current ceramic capacitor to realize suitable DC blocking function.18 Ω output impedance of this balanced-unbalanced transformer are transformed into 50 Ω by 3: 5 turn ratio step-up transformers.This output transformer is made of a transformer coupled auto-transformer post, and it has used the multi-thread copper strips of the ferrite magnetic core material that has high Q, low-loss, appropriate permeability (μ=40).

Should present to each KPT with identical DC feed circuit by separating by negative dc voltage.Each feed network comprises that thereby the inductor-capacitor combination is provided with the RF energy and enters this power supply from this power amplifier, and does not have the RF energy to enter this power amplifier from this power supply or other power supply.This is by a big tandem electric inductance, and promptly a choke and an electric capacity in parallel are realized, a RF shunt capacitance and an other frequency bypass electric capacity.This DC power feed comprises suitable bleeder and detects resistance, is used for protection and current monitoring.

By the invention has been described with reference to selected most preferred embodiment, should be appreciated that the present invention is not limited to these embodiment.On the contrary, those skilled in the art can make more modifications and variations to the present invention under the prerequisite of not violating like scope and spirit of the present invention at the claims defined.

Claims (33)

1. a high power that is used to amplify an allocated frequency band RF power is recommended the RF amplifier, include the RF input, the RF output, the DC power supply, the first and second kw of power transistor devices, each kw of power transistor device comprises heat and conductivity flange, the multiple chips array that constitutes by a plurality of semiconductor elements, each described tube core has a flat low surface, major part on this low surface constitutes drain electrode, in the position of leaving described flat low surface, thereby constitute source electrode and grid respectively and be used for the drain electrode of this tube core is carried out direct heat with described flange and electrically contacted the device that the described flange of arrangement is used for the heat radiation of drain terminal and described tube core; Be used for the RF input drive signal is split into forward phase part and reverse phase partly and the first division apparatus that is coupled with described RF input; Being used for described forward phase partial segmentation with this drive signal becomes a plurality of isolation signals to be used to provide the second splitter device to the grid of the described first kw of power transistor device; Be used for that described reverse phase partly is cleaved into a plurality of isolation signals and be used to provide tripartition apparatus to the grid of the described second kw of power transistor device; Each semiconductor element of the described first kw of power transistor device respectively has a grid one source pole input circuit, this input circuit and the relevant output of the described second splitter device are the RF couplings, and this input circuit floats with respect to the flange of the described first kw of power transistor device; First semiconductor element of the described second kw of power transistor device respectively has a grid one source pole input circuit, this input circuit and the relevant output of described tripartition apparatus are the RF couplings, but this input circuit floats with respect to the flange of the described second kw of power transistor device; Composite set, the input with the source electrode that is coupled to the first and second kw of power transistor devices are used for making up the RF output of being amplified and the RF signal that is exaggerated are offered described RF output; The power supply of DC source voltage; Be connected to the filter apparatus of the power supply of described dc voltage with source electrode with described kw of power transistor device, described filter apparatus comprises the device that is used for blocking from the choke device of the RF signal of the described amplification of described dc voltage power supply and is used for the RF energy that bypass picks up from DC power supply or other circuit.

2. high power RF amplifier as claimed in claim 1, the described choke device of wherein said filter apparatus comprises the RF choke between the source electrode that is serially connected in a device in dc voltage power supply and the described kw of power transistor device.

3. high power RF amplifier as claimed in claim 2, the described device that wherein is used for bypass is included in an inductance and the RF shorted condenser between RF choke and the described source electrode, and this shorted condenser is between the contact of RF ground and this inductance and RF choke.

4. high power RF amplifier as claimed in claim 1, wherein said filter apparatus comprise a series circuit that is made of inductance, RF choke and resistance.

5. high power RF amplifier as claimed in claim 4, wherein said resistance has about 0.01 ohm value.

6. high power RF amplifier as claimed in claim 3, wherein said inductor have value that inductance between the 0.3 and 0.5 μ H and described short circuit capacitance have between about 0.1 and 1 μ f.

7. a high power grounded drain common source RF amplifier includes an input; One dc voltage power supply; One output circuit; With a high power, high voltage large chip transistor, this transistor comprises heat and the conductivity flange with a upper surface, with a semiconductor transistor tube core with lower surface, on the major part of described lower surface, form the drain electrode of this tube core, described drain electrode is directly done contacting of electricity and heat with described flange, constitute source electrode and grid respectively on the described tube core that leaves described flat lower surface, described output circuit is coupled to source electrode; Isolate input stage with a DC, be placed between described input and the described grid, this input stage is floated with respect to described drain electrode; Wherein said input stage includes one and has primary coil that is connected to described input and the isolating transformer with segregate secondary coil of first and second ends that are connected respectively to described grid and described source electrode.

8. RF amplifier circuit as claimed in claim 7, wherein said output circuit include the DC obstruction output stage that is used for passing through the RF signal on a RF frequency band that presets.

9. RF amplifier circuit as claimed in claim 8 includes the RF that described source electrode is connected to described dc voltage power supply and blocks DC and present level.

10. RF amplifier circuit as claimed in claim 9, the wherein said grade RF short-circuiting means that comprises the RF signal that is used for bypass otherwise on described source electrode, is occurred of presenting.

11. RF amplifier circuit as claimed in claim 7, wherein said input stage are included in first end of described secondary coil and the low resistance between the described grid to limit described transistorized gain for unconditional stability.

12. as the RF amplifier circuit of claim 11, wherein said semiconductor element has the input impedance between described source electrode and described grid, and is used for the described resistance of desirable gain and has an ohmic value less than described input impedance.

13. RF amplifier circuit as claimed in claim 7 includes first end that is connected to described secondary coil and a drain electrode-grid feedback circuit of described grounded drain.

14., include the resistance and the electric capacity that are connected in series as the RF amplifier circuit of claim 13.

15. RF amplifier circuit as claimed in claim 7, wherein said semiconductor element has a input impedance between described source electrode and described grid, and include the gate-to-source via resistance that is connected between described source electrode and the described grid, and have and compare very big ohmic value with this input impedance.

16. RF amplifier circuit as claimed in claim 7, wherein said input stage are included in the gate-to-source terminal circuit that an electric capacity and the resistance that is in series between described grid and the described source electrode is constituted.

17. a high power that is used to amplify RF power in an allocated frequency band is recommended the RF amplifier, include the RF input, the RF output, power supply, the first and second kw of power transistor devices, each kw of power transistor device comprises heat and conductivity flange, the multiple chips array that constitutes by a plurality of semiconductor elements, each described tube core has a flat low surface, major part on this low surface constitutes drain electrode, thereby constitute source electrode and grid respectively in the position of leaving described flat low surface and be used for that the drain electrode of this tube core carried out direct heat with described flange and electrically contact settling described flange to be used to drain to dispel the heat and the device of the heat radiation of described tube core; Be used for the RF input drive signal is split into forward phase part and reverse phase partly and the first division apparatus that is coupled with described RF input; Being used for described forward phase partial segmentation with this drive signal becomes a plurality of isolation signals to be used to provide the second splitter device to the grid of the described first kw of power transistor device; Be used for that described reverse phase partly is cleaved into a plurality of isolation signals and be used to provide tripartition apparatus to the grid of the described second kw of power transistor device; Each semiconductor element of the described first kw of power transistor device respectively has a grid one source pole input circuit, this input circuit and the relevant output of the described second splitter device are the RF couplings, and this input circuit suspends with respect to the flange of the described first kw of power transistor device; First semiconductor element of the described second kw of power transistor device respectively has a grid one source pole input circuit, this input circuit and the relevant output of described tripartition apparatus are the RF couplings, but this input circuit floats with respect to the flange of the described second kw of power transistor device; Composite set, the input with the source electrode that is coupled to the first and second kw of power transistor devices are used for making up the RF output of being amplified and the RF signal inciting somebody to action, be exaggerated offers described RF output; The power supply of DC source voltage; Be connected to the DC feeding means of described dc voltage power supply with source electrode with described kw of power transistor device, described DC feeding means comprises the choke device that is used for blocking from the described RF of the being exaggerated signal of described dc voltage power supply, with be used for the device of bypass RF energy, wherein four of each described kw of power transistor device tube cores mate by parallel connection externally and by DC, thereby their gate-to-source threshold value is matched within 0.2 volt, their drain source resistance mated within 8% and their forward transconductance be within 1 Siemens.

18. high power RF amplifier as claim 17, four tube cores that wherein are used for each described kw of power transistor device are selected from the adjacent chip position on identical semiconductor wafer, to guarantee that good temperature and current tracking are arranged between four tube cores.

19. high power RF amplifier as claim 17, four groups of tube cores that the wherein said first and second kw of power transistor devices have are selected from the adjacent chips position of single semiconductor wafer, to guarantee from one to another described kw of power transistor good temperature and current tracking being arranged.

20. as the high power RF amplifier of claim 19, wherein the difference of the average RF gain between the first and second kw of power transistor devices is within about 0.5db.

21. as the high power RF amplifier of claim 19, wherein the difference of the RF efficient between the first and second kw of power transistor devices is within about 1%.

22. high power RF amplifier as claim 17, wherein said first division apparatus is directly coupled to the second splitter device and the first kw of power transistor device, and sensed the tripartition apparatus and the second kw of power transistor device of being coupled to; And the average gain threshold value that the first kw of power transistor device has will be higher than the average gain threshold value of the second kw of power transistor device.

23. as the high power RF amplifier of claim 22, wherein the average gain threshold value of this first kw of power transistor device is than high about 0.2 to 0.4 volt of the average gain threshold value of the second kw of power transistor device.

24. as the high power RF amplifier of claim 17, wherein each tube core of each described first and second kw of power transistor device has about 1 to 2 ohm grid input resistance of series connection separately.

25. high power RF amplifier as claim 17, wherein each tube core of each described first and second kw of power transistor device has at its grid and the end of the RF of input separately between its source electrode, and each in the described input RF end all is made of the resistance-capacitance combination of series connection.

26. as the high power RF amplifier of claim 17, wherein each tube core of each described first and second kw of power transistor device has source electrode and the end of the DC separately between its grid resistance at it, this DC end resistance has the value of 30 to 40K Ω.

27. high power RF amplifier as claim 17, wherein each tube core of each described first and second kw of power transistor device has source electrode-drain electrode RF feedback circuit separately, each described RF feedback circuit is made of a resistance-capacitance tandem compound, has the resistance of a resistance at 400 to 560 Ω.

28. as the high power RF amplifier of claim 17, the source electrode of each of wherein said kilowatt of transistor device directly is parallel-connected to described combiner apparatus.

29. as the high power RF amplifier of claim 28, wherein said combiner apparatus comprises that one has the output balanced-unbalanced transformer transformer of 18 Ω layer impedances.

30. as the high power RF amplifier of claim 17, each of the described first and second kw of power transistor devices comprises that further one is used for the resonant circuit to the source electrode that the is combined-drain electrode output capacitance dynamic compensation of the tube core of each kw of power transistor device; Described resonant circuit is included in the combination of the series connection of one between source electrode and ground inductor-capacitor and flows there to allow resonance circulation RF electric current.

31. high power RF amplifier as claim 17, wherein said DC feeding means comprises separately an inductor-capacitor combination that is used for each described first and second kilowatts of transistor device, be included in the parallel connection combination of the series connection inductance of one between described power supply and the described transistor device of kw of power separately and RF electric capacity and frequency bypass electric capacity.

32. as the high power RF amplifier of claim 29, the impedance of wherein exporting the balanced-unbalanced transformer transformer is mated to 50 Ω from 18 Ω, has single 3.5 turn ratio transformers or a pair of 2: 3 turn ratio transformers, is lower than 1.25: 1 VSWR.

33. as the high power RF amplifier of claim 17, further comprise a low-pass/high-pass duplexer filter structure that is placed between described combiner apparatus and the described RF output, be used for reducing harmonic distortion and dissipation harmonic wave end is provided.

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